ASTRO-NUTS nylon axle nuts are not only the easiest way to reduce weight on your skates, but also a fun, new way to express yourself by personalizing your skates with various colors. ASTRO-NUTS feature a 100% molded, nylon construction which makes them 3 times lighter, and equally as strong as standard axle nuts. With ASTRO-NUTS in so many colors, you can have a different set for every day of the week.